Title :
A Mismatch Detector for Adaptive Antenna Impedance Matching
Author :
Meng, Fanfan ; van Bezooijen, A. ; Mahmoudi, Reza
Author_Institution :
Philips Semicond., Nijmegen
Abstract :
The efficiency of a mobile phone´s power amplifier suffers from the antenna impedance mismatch caused by the body-effect of its user. A mismatch detector used for an innovative antenna matching algorithm which is based on adaptive correction of the reactive part of the antenna impedance mismatch has been designed, implemented and measured. The mismatch detector which consists of a wideband 90deg phase shifter, a limiter and a Gilbert-cell multiplier detects the phase of the reflection coefficient. The dynamic range of the mismatch detector is up to 142deg at the standard GSM frequencies (900MHz, 1800MHz and 1900MHz) for input power not less than -20dBm. This mismatch detector fulfills the function of determining the mismatch property according to the presented adaptive antenna impedance matching algorithm
Keywords :
adaptive antenna arrays; impedance matching; mobile handsets; phase detectors; power amplifiers; 1800 MHz; 1900 MHz; 900 MHz; GSM frequencies; Gilbert-cell multiplier; MMIC mixers; adaptive antenna impedance matching; adaptive control; adaptive correction; antenna impedance mismatch; antenna matching algorithm; body-effect; limiter; microwave detectors; mismatch detector; mobile phone power amplifier; phase detection; power amplifiers; reflection coefficient; wideband 90deg phase shifter; Adaptive arrays; Algorithm design and analysis; Antenna accessories; Antenna measurements; Detectors; Impedance matching; Impedance measurement; Mobile antennas; Phase detection; Power amplifiers; MMIC mixers; Power amplifiers; adaptive control; microwave detectors; phase detection;
Conference_Titel :
Microwave Conference, 2006. 36th European
Conference_Location :
Manchester
Print_ISBN :
2-9600551-6-0
DOI :
10.1109/EUMC.2006.281332
